What you're asking for is a .357 Magnum load. Published .38-44 loads max out at about 1250 ft/sec muzzle velocity with a 158 grain bullet and develop about 25,000 psi. To get to 1400 ft/sec, you would have to get into .357 Magnum pressures. I have a pre-war Outdoorsman also and I wouldn't subject it to .357 Magnum pressures.